Table 1: Local Synovial Effect Induced in PsA Clinical Trials

Compound	Main Target	Effect on Psoriatic Synovium	Refs.
Methotrexate	T lymphocytes	Reduction of synovial layer thickness	[15, 17]
	Macrophages	Reduction of CD3, CD4, CD8, CD68 sublining infiltration
	? others	Reduction of polyclonal, inflammation-related CD4+ T cells, smaller effect on oligoclonal CD8 T cells
Infliximab	TNF	Reduction of synovial layer thickness	[22-24, 26,28]
		Reduction of vascularity and endothelial cell activation
Adalimumab	TNF	Reduction of the synovial layer thickness	[27]
		Reduction of CD3 infiltration
		Reduction of MMP-13 expression
Etanercept	TNF, lymphotoxin	Reduction of the synovial layer thickness	[11]
		Reduction of CD68+ and CD163+ macrophages
		Reduction of MMP-3 and MMP-9